The official G9 help thread

[tmuikku]

...
Anyways, the bulk-buy isn't the issue here any more. I've managed to find all the parts on Mouser, the only problem is the lead time is around 20 weeks for a few capacitors in my order. I can't seem to find any way around this and I'd like to stick with the same manufacturer for the capacitors.

I guess I'll have to keep on searching :/

Thanks once again

Well, just post which capacitors (designations on schematics) and people will suggest alternatives!

 

[braeden]

Mouser #:	505-MKS20.022/63/5	
Mfr. #:	MKS2-.022/63/5

Mouser #:	75-MKT1813410014	
Mfr. #:	MKT1813410014

2 71-CCF2-J-1K               Vishay/Dale 1.0K 2W 5% Metal Film  (R31,R131)
2 71-CCF02-J-470/R         Vishay/Dale 470R 2W 5% Metal Film  (R33,R37)
1 71-CPF2-F-100K            Vishay/Dale 100K 2W 1% Metal Film  (R34)

Cheers :'(

 

[tmuikku]

Mouser #:	505-MKS20.022/63/5	
Mfr. #:	MKS2-.022/63/5

Mouser #:	75-MKT1813410014	
Mfr. #:	MKT1813410014

2 71-CCF2-J-1K               Vishay/Dale 1.0K 2W 5% Metal Film  (R31,R131)
2 71-CCF02-J-470/R         Vishay/Dale 470R 2W 5% Metal Film  (R33,R37)
1 71-CPF2-F-100K            Vishay/Dale 100K 2W 1% Metal Film  (R34)

Cheers :'(

For those capacitors you can use any other 22nf and 10nf film caps ( aren't they the highpass filter caps, C8 and C9?). They are on the conrol PCB which has three different holes for different size caps (lead spacing). I'm not sure if you could even fit that radial cap in there? If you want Wima brand Banzai usually have them in stock. http://www.banzaimusic.com/MKS2-5mm/ . I'm almost sure that you can find those resistors too from Banzai You can use any brand resistors with proper wattage rating and resistanse.

 

[braeden]

Ahh Banzai Music, life saver, and the shipping costs aren't too bad either.
Cheers!

 

[grantlack]

Took a good dive into the various G9 threads and never found an answer on this. Is the use of rotaries essential (i.e. are we wanting a shorting style to prevent pops) or is it purely an elegance/ease of build sort of deal? Hoping to condense the frontpanel with some pushbuttons and toggles for a hair-brained scheme, but I figured I'd consult before I get all crazy buying parts.

 

[JBVries]

For anyone starting to build the G9 here is a link to the Mouser ordering form that has been updated to correct out of production or obsolete parts. This is taken right from the PDF I found that Skyler compiled. Cheers!!

http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=b61a0b8df9

 

[lampodigenio]

Hi,
I have a noise's problem. (hum???) I've recorded it. Can you help me please?

http://www.antonellodurso.com/hum.wav

Thank's

 

[tmuikku]

Hi,
I have a noise's problem. (hum???) I've recorded it. Can you help me please?

http://www.antonellodurso.com/hum.wav

Thank's

Hi there!

Have you tried building the HT power supply of board? Check with FFT software what frequency the hum is. If it is mainly 50Hz it is the mains transformer induced hum (tidy your wiring, move mains transformer around). If mostly 100Hz and up it is caused by PCB layout and building external HT supply will help. Check out this thread a few pages back and try search, plenty of info!

Best,
Teemu

edit: not heater supply but the HT supply!

 

[lampodigenio]

Is this 100Hz?
Do you think I should build external heater supply?
Thanks

 

[tmuikku]

Is this 100Hz?
Do you think I should build external heater supply?
Thanks

Indeed, there is some layout issues in G9 pcb and building separate HT supply seems to reduce most if not all of the 100hz hum. MeToo2 posted some pictures.
http://www.groupdiy.com/index.php?topic=17980.msg511680#msg511680

edit: not heater supply but the HT supply!

 

[electrisizer]

by the way - same problem here  : 100Hz hum
- i build a new supply next month

 

[haima]

i had 100hz (+ harmonics) hum problems until i made a external (i.e not on the main pcb) high voltage supply - the heater supply was NOT the problem for me, and i believe this is the case for others too?

press "print" and then you can use the search function of your browser to find the info... it's all there in previous pages.

 

[tmuikku]

i had 100hz (+ harmonics) hum problems until i made a external (i.e not on the main pcb) high voltage supply - the heater supply was NOT the problem for me, and i believe this is the case for others too?

press "print" and then you can use the search function of your browser to find the info... it's all there in previous pages.

Ohops, you are correct! I ment the HT supply also, not heater! Fixed my messages above.

 

[lampodigenio]

edit: not heater supply but the B+!

What's B+

The hum in my picture is 100Hz???

Where I find heater HT Supply?

 

[tmuikku]

edit: not heater supply but the B+!

What's B+

The hum in my picture is 100Hz???

Where I find heater HT Supply?

Shit I'm bad with forums Look at G9 schematics. There is separate circuits for heater, HT and phantom. B+ = HT. No such thing as heater HT supply, they are separate.

 

[lampodigenio]

I built the external PSU but I do not know where I have to be wired "heater out" and "Cap 2 out" as shown. Could you help me?

Instead of BR1 and BR2 I used two bridges of 1.5 A. is that correct?

Why cap2 is 245V?

Thanks

 

[haima]

Why cap2 is 245V?

i believe the "245v" refers to the fact that this is the OUTPUT for the high voltage section of the power supply - which is intended to be around 245v.

you should use a 350v capacitor for "cap2", the same as "cap1"

you also take the high voltage output from this capacitor/that point on the PCB.

check the schematic for the G9 - it's all there....

good luck! and be very careful of the high voltage!! always discharge the caps before working on the unit.

 

[lampodigenio]

Excuse me but I did not understand what I do. Where I should wire the cap2 wiring? And heater out?

 

[microc]

I've just Morgan Jones books; Valve Amplifiers and Building Valve Amplifiers, great books btw!
I'm also designing a new PSU for the G9. I see a lot of different designs in here. If we follow Mr. Jones we should have all PSU parts on a different board, and screen the board from the rest of the amplifier, even tho the current is very low, and the star-connect every part that needs power. The 12V, 48V and 245V should be place separably from the main board, and no trace on the main board should be used for power. Star-connected heather etc.

any comments? Have somebody done this?
I have drawn a board in autoCAD and will try when I get my next payment, or maybe in January... x-mas gifts....

 

[lampodigenio]

anyone help me?